Display device

ABSTRACT

According to one embodiment, a display device includes a first display panel, a second display panel and an adhesive layer which adheres the first and second display panels. The first display panel includes a first scanning line, a first signal line, a first pixel electrically connected to the first scanning line and the first signal line, and the first pixel includes a first pixel electrode including first line portions extending parallel to the first signal line. The second display panel includes a second scanning line, a second signal line, and a second pixel electrically connected to the second scanning line and the second signal line, and the second pixel includes a second pixel electrode including second line portions intersecting the second signal line in plan view.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2021-097194, filed Jun. 10, 2021, theentire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a display device.

BACKGROUND

In recent years, a technology has been developed that uses a displaypanel for dimming in addition to a display panel for displaying imagesin order to improve the contrast of display devices, and there is ademand of further improving the display quality of display devicesconfigured by using this technology.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a configuration example of adisplay device comprising two display panels.

FIG. 2 is a cross-sectional view schematically showing a configurationof the display device shown in FIG. 1 .

FIG. 3 is a cross-sectional view showing the display device shown inFIG. 2 in more detail.

FIG. 4 is a plan view showing pixels arranged in a liquid crystaldisplay panel according to one embodiment.

FIG. 5 is a plan view of pixels arranged in a dimming panel of the sameembodiment in detail.

FIG. 6 is a plan view showing a part of two adjacent pixel electrodesdisposed in a liquid crystal display panel and a part of two adjacentpixel electrodes disposed in a dimming panel in the same embodiment.

FIG. 7 is a plan view showing a shape of a light-shielding film disposedin the dimming panel in the same embodiment.

FIG. 8 is a plan view showing another shape of the light-shielding filmdisposed in the dimming panel in the same embodiment.

FIG. 9 is a plan view showing still another shape of the light-shieldingfilm disposed in the dimming panel in the same embodiment.

FIG. 10 is a plan view showing pixels disposed in a dimming panelaccording to a comparative example.

FIG. 11 is another plan view showing in detail the pixels disposed inthe dimming panel in to the same embodiment.

DETAILED DESCRIPTION

In general, according to one embodiment, a display device comprises afirst display panel including a display area for displaying images, asecond display panel including a dimming area for controlling brightnessof the display area and an adhesive layer which adheres the firstdisplay panel and the second display panel to each other. The firstdisplay panel comprises a first scanning line extending along a firstdirection, a first signal line extending in a second directionintersecting the first direction while bending in a first bendingdirection, a first pixel electrically connected to the first scanningline and the first signal line, and the first pixel includes a firstpixel electrode including a plurality of first line portions extendingparallel to the first signal line. The second display panel comprises asecond scanning line extending along the first direction, a secondsignal line extending in the second direction while bending in a secondbending direction, and a second pixel electrically connected to thesecond scanning line and the second signal line, and the second pixelincludes a second pixel electrode including a plurality of second lineportions intersecting the second signal line in plan view.

Embodiments will be described hereinafter with reference to theaccompanying drawings.

The disclosure is merely an example, and proper changes within thespirit of the invention, which are easily conceivable by a skilledperson, are included in the scope of the invention as a matter ofcourse. In addition, in some cases, in order to make the descriptionclearer, the widths, thicknesses, shapes, etc., of the respective partsare schematically illustrated in the drawings, compared to the actualmodes. However, the schematic illustration is merely an example, andadds no restrictions to the interpretation of the invention. Besides, inthe specification and drawings, the same or similar elements as or tothose described in connection with preceding drawings or thoseexhibiting similar functions are denoted by like reference numerals, anda detailed description thereof is omitted unless otherwise necessary.

FIG. 1 is an exploded perspective view schematically showing aconfiguration of a display device DSP1 comprising two display panels.FIG. 1 illustrates a three-dimensional space defined by a firstdirection X, a second direction Y perpendicular to the first direction Xand a third direction Z perpendicular to the first direction X and thesecond direction Y. Note that the first direction X and the seconddirection Y are orthogonal to each other, but may intersect at an angleother than 90 degrees. In the following descriptions, the thirddirection Z is defined as “upward” and a direction opposite to the thirddirection is defined as “downward”. Further, with such expressions “asecond member above a first member” and “a second member below a firstmember”, the second member may be in contact with the first member ormay be remote from the first member. In addition, it is assumed thatthere is an observation position to observe the display device DSP on atip side of an arrow in a third direction Z, and viewing from thisobservation position toward the X-Y plane defined by the first directionX and the second direction Y is referred to as a planar view.

As shown in FIG. 1 , the display device DSP comprises a liquid crystaldisplay panel PNL1 (a first display panel), a dimming panel PNL2 (asecond display panel) and a backlight unit BL. As shown in FIG. 1 , thedimming panel PNL2 is placed between the liquid crystal display panelPNL1 and the backlight unit BL, and with this structure, the contrast ofimages displayed on the liquid crystal display panel PNL1 can beimproved.

The liquid crystal display panel PNL1 is, for example, rectangular inshape. In the illustrated example, the liquid crystal display panel PNL1includes a short edge EX parallel to the first direction X and theliquid crystal display panel PNL1 has a long edge EY parallel to thesecond direction Y. The third direction Z corresponds to the thicknessdirection of the liquid crystal display panel PNL1. A main surface ofthe liquid crystal display panel PNL1 is parallel to the X-Y planedefined by the first direction X and the second direction Y. The liquidcrystal display panel PNL1 includes a display area DA and a peripheralarea SA located on an outer side of the display area DA. The peripheralarea SA includes a terminal area MT in which a driver IC and a flexibleprinted circuit board are mounted. In FIG. 1 , the terminal area MT isindicated by shaded lines.

The display area DA is an area on which images are displayed andcomprises a plurality of pixels PX arranged in a matrix, for example. Asenlargedly shown in FIG. 1 , each pixel PX is electrically connected toa respective scanning line GL and a respective signal line SL, andcomprises a switching element SW, a pixel electrode PE, a commonelectrode CE, a liquid crystal layer LC and the like.

The switching element SW is constituted by a thin-film transistor (TFT),for example, and is electrically connected to a respective scanning lineGL and a respective signal line SL. The scanning line GL is electricallyconnected to the switching element SW in each of those pixels PX alignedalong the first direction X. The signal line SL is electricallyconnected to the switching element SW in each of the pixels PX alignedalong the second direction Y. The pixel electrodes PE are connected tothe switching elements SW, respectively. Each of the pixel electrodes PEopposes the common electrode CE, and the liquid crystal layer LC isdriven by the electric field generated between the respective pixelelectrode PE. A capacitance CS is formed, for example, between theelectrode at the same potential as that of the common electrode CE andthe electrode at the same potential as that of the pixel electrode PE.

The terminal area MT extends along the short side EX of the liquidcrystal display panel PNL1. Terminal portions are formed in the terminalarea MT, and the liquid crystal display panel PNL1 is electricallyconnected via the terminal portions to, for example, an external devicesuch as a flexible printed circuit board and the like.

Although the detailed configuration is omitted from the illustration inFIG. 1 , the dimming panel PNL2 has basically the same configuration asthat of the liquid crystal display panel PNL1. The configuration thatpartially differs between the liquid crystal display panel PNL1 and thedimming panel PNL2 is shown in FIGS. 2 and 3 , as will be describedbelow.

The backlight unit BL is located below the dimming panel PNL2, and thelight from the backlight unit BL is controlled for every pixel PX, thusdisplaying images.

FIG. 2 is a schematic cross-sectional view showing the configuration ofthe display device DSP shown in FIG. 1 .

As described above along with the description of FIG. 1 , the displayunit DSP comprise a liquid crystal display panel PNL 1, a dimming panelPNL2 and a backlight unit BL. Note that in FIG. 2 , the illustration ofthe backlight unit BL is omitted. The liquid crystal display panel PNL1and the dimming panel PNL2 are adhered together with, for example, atransparent adhesive layer OCA. The common configuration between theliquid crystal display panel PNL1 and the dimming panel PNL2 ispositioned so that they overlap each other in planar view and adhered bythe adhesive layer OCA.

In the following descriptions, the configuration of the liquid crystaldisplay panel PNL1 will be first described.

As shown in FIG. 2 , the liquid crystal display panel PNL1 comprises afirst substrate SUB11, a second substrate SUB 21, a liquid crystal layerLC1, a first polarizer PL11 and a second polarizer PL21.

The liquid crystal layer LC1 is sandwiched between the first substrateSUB11 and the second substrate SUB21 and sealed by the sealant SE 1. Thefirst polarizer PL11 is placed under the first substrate SUB 11, and thesecond polarizer PL21 is placed above the second substrate SUB21. Thefirst polarizer PL11 and the second polarizer PL21 include polarizationaxes which are positioned, for example, in a cross-Nicol relationship,that is, 90 degrees.

The terminal area MT1 of the liquid crystal display panel PNL1 containsthe driver IC1 and the flexible printed circuit board FPC1 mountedthereon. The driver IC1 and the flexible printed circuit board FPC1mounted on the terminal area MT1 are covered by a protective film PF1.

Next, the configuration of the dimming panel PNL2 will be described.

As shown in FIG. 2 , the dimming panel PNL2, as in the case of theliquid crystal display panel PNL1, comprises a first substrate SUB12, asecond substrate SUB22, a liquid crystal layer LC2, a first polarizerPL12 and a second polarizer PL22.

The liquid crystal layer LC2 is sandwiched between the first substrateSUB12 and the second substrate SUB22, and sealed by a sealant SE2. Thefirst polarizer PL12 is disposed under the first substrate SUB12 and thesecond polarizer PL22 is disposed above the second substrate SUB22. Thefirst polarizer PL12 and the second polarizer PL22 have polarizationaxes arranged, for example, in a cross-Nicol relationship, that is, 90degrees. Further, the polarization axis of the first polarizer PL1 ofthe liquid crystal display panel PNL1 and the polarization axis of thesecond polarizer PL22 of the dimming panel PNL2 are directed in the samedirection.

The terminal area MT2 of the dimming panel PNL2 contains the driver IC2and the flexible printed circuit board FPC2 mounted therein. The driverIC2 and the flexible printed circuit board FPC2 mounted in the terminalarea MT2 are covered by a protective film PF2.

Here, the configuration of the display device DSP will now be describedin more detail with reference to the cross-sectional view shown in FIG.3 .

In the following descriptions, the configuration of the liquid crystaldisplay panel PNL1 will first be described in detail.

As described above with the description of FIG. 2 , the liquid crystaldisplay panel PNL1 comprises a first substrate SUB11, a second substrateSUB 21, a liquid crystal layer LC1, a first polarizer PL1 1 and a secondpolarizer PL21.

As shown in FIG. 3 , the first substrate SUB11 comprises a firsttransparent substrate 11 and an alignment film AL11. In addition to theconfiguration described above, the first substrate SUB11 includes, forexample, a scanning line GL (in more detail, scanning line GL1, whichwill be described later), a signal line SL (in more detail, signal lineSL1 described later), a switching element SW, a pixel electrode PE(pixel electrode PE1, which will be described later), a common electrodeCE and the like, shown in FIG. 1 , but the illustrations of these areomitted from FIG. 3 .

The transparent substrate 11 includes a main surface (lower surface) 11Aand a main surface 11 The first transparent substrate 11 has a mainsurface (lower surface) 11A and a main surface (upper surface) 11B on anopposite side to the main surface 11A. On the main surface 11B side ofthe first transparent substrate 11, scanning lines GL, signal lines SL,switching elements SW, pixel electrodes PE, common electrode CE and thelike are provided. On the main surface 11B side of the first transparentsubstrate 11, an alignment film AL11 is further provided to be incontact with the liquid crystal layer LC1. On the main surface 11A sideof the first transparent substrate 11, the first polarizer PL11 isadhered.

As shown in FIG. 3 , the second substrate SUB21 comprises a secondtransparent substrate 21, a light-shielding film BM1, color filters CF,an overcoat film OC and an alignment film AL21. The light-shielding filmBM1 may be referred to as a light-shielding pattern.

The second transparent substrate 21 includes a main surface (lowersurface) 21A and a main surface (upper surface) 21A on an opposite sideto the main surface 21A. The main surface 21A of the second transparentsubstrate 21 opposes the main surface 11B of the first transparentsubstrate 11. The light-shielding film BM1 is provided on the mainsurface 21A side of the second transparent substrate 21 and, as in thecase of the scanning lines GL and the signal lines SL, the pixels PX (inmore detail, pixel PX1) are compartmentalized. The color filter CFpartially overlaps the light-shielding film BM1. The color filter CFincludes a red color filter CFR, a green color filter CFG, a blue colorfilter CFB and the like. The overcoat film OC covers the color filtersCF. The overcoat film OC can prevent the pigments of the color filtersCF from leaking into the liquid crystal layer LC1. The alignment filmAL21 covers the overcoat film OC and is in contact with the liquidcrystal layer LC1. On the main surface 21B side of the secondtransparent substrate 21, the second polarizer PL21 is adhered.

The first transparent substrate 11 and the second transparent substrate21 are, for example, insulating substrates such as glass substrates orplastic substrates. The light shielding film BM1 should preferably beformed of a black resin in which black pigments or the like aredispersed. The alignment films AL11 and AL21 are horizontal alignmentfilm having an alignment restriction force parallel to the X-Y plane.The alignment restriction force may be imparted by a rubbing process ora photo-alignment process.

Next, the configuration of the dimming panel PNL2 will be described indetail.

As described above with the description of FIG. 2 , the dimming panelPNL2 comprises a first substrate SUB12, a second substrate SUB22, aliquid crystal layer LC2, a first polarizer PL12 and a second polarizerPL22.

As shown in FIG. 3 , the first substrate SUB12 comprises a firsttransparent substrate 12 and an alignment film AL12. In addition to theconfiguration described above, the first substrate SUB12 includes ascanning line GL (in more detail, scanning line GL2, which will bedescribed later), a signal line SL (in more detail, signal line SL2,which will be described later), a switching element SW, a pixelelectrode PE (in more detail, pixel electrode PE2, which will bedescribed later), a common electrode CE and the like as in the case ofthe liquid crystal display panel PNL1, but the illustrations of theseare omitted from FIG. 3 .

The first transparent substrate 12 includes a main surface (lowersurface) 12A and a main surface (upper surface) 12B on an opposite sideto the main surface 12A. On the main surface 12B side of the firsttransparent substrate 12, scanning lines GL and signal lines SL,switching elements SW, pixel electrodes PE, common electrodes CE and thelike provided. On the main surface 12B side of the transparent substrate12, an alignment film AL12 is further provided to be in contact with theliquid crystal layer LC. On the main surface 12A side of the firsttransparent substrate 12, the first polarizer PL12 is adhered.

As shown in FIG. 3 , the second substrate SUB22 comprises a secondtransparent substrate 22, a light-shielding film BM2 and an alignmentfilm AL22. The light-shielding film BM2 may be referred to as alight-shielding pattern as in the case of the light shading film BM1.

Unlike the liquid crystal display panel PNL1, the object of the dimmingpanel PNL2 is to control the brightness. Here, there is no need to formcolor images, and therefore no color filter CF is provided on the secondsubstrate SUB22 of the dimming panel PNL2. Further, the dimming panelPNL2 differs from the liquid crystal display panel PNL1 as well in thatthe overcoat film OC is not provided. This is because there is no needto inhibit pigment (resin) from leaking to the liquid crystal layer LC2due to the fact that a color filter CF is not provided as describedabove.

The second transparent substrate 22 includes a main surface (lowersurface) 22A and a main surface (upper surface) 22B on an opposite sideto the main surface 22A. The main surface 22A of the second transparentsubstrate 22 opposes the main surface 12B of the first transparentsubstrate 12. The light-shielding film BM2 is provided on the mainsurface 22A side of the second transparent substrate 22. The alignmentfilm AL22 covers the light-shielding film BM2 and is in contact with theliquid crystal layer LC2. On the main surface 22B side of the secondtransparent substrate 22, the second polarizer PL22 is adhered.

FIG. 3 shows the case where the light shielding film BM2 is provided onthe second transparent substrate 22 side as an example. But, thestructure is not limited to this, but the light-shielding film BM2 maybe provided on the transparent substrate 12 side. Unlike thelight-shielding film BM1 of the liquid crystal display panel PNL1, thelight-shielding film BM2 may be formed of an opaque metal material suchas molybdenum (Mo), aluminum (Al), tungsten (W), titanium (Ti), titanium(Ti), silver (Ag) or the like, or may be formed of a black resin inwhich black pigments or the like are dispersed, as in the case of thelight-shielding film BM1. When the light-shielding film BM2 is formed ofan opaque metal material, the light-shielding film BM2 may be connectedto the common electrode CE. With this configuration, the resistancevalue of the common electrode CE formed of ITO or the like can be keptlow.

The first transparent substrate 12 and the second transparent substrate22 are, for example, insulating substrates such as glass substrates orplastic substrates. The alignment films AL12 and AL22 are horizontalalignment films having an alignment restriction force substantiallyparallel to the X-Y plane. The alignment restriction force may beimparted by a rubbing treatment or a photo-alignment treatment.

The liquid crystal display panel PNL1 and the dimming panel PNL2 areadhered together by, for example, a transparent adhesive layer OCA. Thecommon configuration between the liquid crystal display panel PNL1 andthe dimming panel PNL2 is positioned by adjustment to overlap each otherin plan view, and is adhered to the adhesive layer OCA.

The backlight unit BL is disposed below the dimming panel PNL2. As thebacklight unit BL, various forms of backlight units can be used, such asthose using light-emitting diodes (LEDs) as the light source, one usinga cold cathode fluorescent lamp (CCFL), and the like. Note that althoughomitted from the illustration in FIG. 3 , a cover member and the likemay be disposed on the second polarizer PL21 of the liquid crystaldisplay panel PNL1.

FIG. 4 is a plan view showing in detail the pixel PX1 disposed in thedisplay area DA of the liquid crystal display panel PNL1. FIG. 4 showsone of a number of pixels PX1 arranged in the display area DA of theliquid crystal display panel PNL1.

In the display area DA of the liquid crystal display panel PNL1, a largenumber of pixels PX1 are arranged in a matrix. As shown in FIG. 4 , eachpixel PX1 includes red (R), green (G) and blue (B) sub-pixels PXR, PXGand PXB. The scanning line GL1 (the first scanning line) disposedbetween the pixels PX1 aligned along the second direction Y. The signalline SL1 (the first signal line) is disposed between sub-pixels PXR, PXGand PXB aligned along in the first direction X. The scanning lines GL1extend in the first direction X and are aligned to be spaced apart fromeach other along the second direction Y. The signal lines SL1 extendalong the second direction Y while bending in directions d1 and d2,which intersect the second direction Y, and are aligned to be spacedapart from each other along the first direction X. In this embodiment,an angle made between the second direction Y and the directions d1 andd2 is defined as el. Note that the direction which makes an angle withthe second direction Y is θ1 may be referred to as a first bendingdirection.

The sub-pixels PXR, PXG and PXB contained in each pixel PX1 includerespective pixel electrodes PE1 (first pixel electrodes) of the sameshape. Each pixel electrode PE1 is located in an area surrounded by twoscanning lines GL1 and two signal lines SL1, respectively. Each pixelelectrode PE1 includes a plurality of line portions LP1 (first lineportions) aligned along the first direction X. The line portions LP1 arearranged to be spaced apart from each other at equal intervals along thefirst direction X. The line portions LP1 each extend along the seconddirection Y while bending in the directions d1 and d2 that intersect thefirst direction X. In other words, the line portions LP1 each extendparallel to the signal lines SL1, and the bending shape of the signallines SL1 is the same as the bending shape of the line portions LP1 (thebending shape of the pixel electrodes PE1).

FIG. 5 is a plan view of the pixel PX2 located in the dimming area CA ofthe dimming panel PNL2. Note that FIG. 5 shows one of a number of pixelsPX2 disposed in the dimming area CA of the dimming panel PNL2.

The dimming area CA of the dimming panel PNL2 is an area equivalent tothe display area DA of the liquid crystal display panel PNL1 andoverlaps the display area DA in plan view. In the dimming area CA, anumber of pixels PX2 are arranged in a matrix. Unlike the liquid crystaldisplay panel PNL1, an object of the dimming panel PNL2 is to controlthe brightness. Here, there is no need to form color images, andtherefore no color filter CF is provided on the dimming panel PNL2 asdescribed before. In other words, the pixel PX2 is different from thepixel PX1 of the liquid crystal display panel PNL1 in that it does notcontain sub-pixels.

As shown in FIG. 5 , the scanning lines GL2 (the second scanning line)each extend in the first direction X and arranged to be spaced apartfrom each other along the second direction Y. The signal lines SL2 (thesecond signal lines) extend along the second direction Y while bendingin directions d3 and d4, which intersect the second direction Y, and arealigned at intervals along the first direction X. The signal lines SL2(the second signal lines) are bent in a direction opposite to thedirection of the signal lines SL1 of the liquid crystal display panelPNL1. In more detail, the signal lines SL1 of the liquid crystal displaypanel PNL1 are bent into an L shape, whereas the signal lines SL2 of theliquid crystal display panel PNL2 are bent is bent into a reversed Lshape. In this embodiment, an angle made between the second direction Yand the directions d3 and d4 is defined as θ2. The angle θ2 exhibits avalue larger than that of the angle θ1 mentioned above, and the signallines SL2 are slightly inclined as compared to the signal lines SL1 ofthe liquid crystal display panel PNL1. Note that the direction whoseangle with the second direction Y is θ2 may be referred to as the secondbending direction.

Between two adjacent signal lines SL2 spaced apart from each other alongthe first direction X, a dummy signal line D SL is disposed. The dummysignal line DSL, as in the case of the signal lines SL2, extends in thesecond direction Y while bending in the directions d3 and d4. Asdescribed, the dummy signal line DSL thus disposed between two adjacentsignal lines SL2 spaced apart from each other along the first directionX, it is possible to suppress the degradation of display quality causedby parallax displacement which can occur due to the overlapping of twodisplay panels.

The pixel PX2 includes pixel electrodes PE2 (second pixel electrode). Asenlargedly shown in FIG. 5 , a pixel electrode PE2 is connected to theswitching element SW via an opening OP SW and is electrically connectedto the respective scanning line GL2 and the respective signal line SL2.Note that it is here assumed the case where the switching element SW isof a bottom-gate type TFT, but it is not limited to this. It may be of atop-gate type TFT.

The pixel electrode PE2 includes a plurality of line portions LP2(second line portions) arranged along the first direction X. The lineportions LP2 are disposed to be spaced apart from each other at equalintervals along the first direction X. The line portions LP2 each extendalong the second direction Y while bending in the directions d1 and d2which intersect the second direction Y. That is, the line portions LP2has a shape similar to that of the line portions LP1 which constitutethe pixel electrode PE1 of the liquid crystal display panel PNL1. Thus,when the bending shape of each line portions LP1 contained in the pixelelectrode PE1 and the bending shape of each line portions LP2 containedin the pixel electrode LP2 are made similar to each other, it ispossible to prevent the pixel electrode PE1 and the pixel electrode PE2from being misaligned when the liquid crystal display panel PNL1 and thedimming panel PNL2 are superimposed.

As shown in FIG. 5 , the line portions LP2 contained in the pixelelectrode PE2 intersect the signal lines SL2 in plan view, which areelectrically connected thereto. In more detail, the line portions LP2extend along the second direction Y so as to cross (straddle) the signallines SL2 in plan view, which are electrically connected thereto. Thebending shape of the signal lines SL2 and the bending shape of the lineportions LP2 (the bending shape of the pixel electrodes PE2) isdifferent from each other in the bending direction and the angle withrespect to the second direction Y (bending angle).

In this embodiment, it is assumed that the pixels PX2 of the dimmingpanel PNL2 have the same area as that of the pixels PX1 of the liquidcrystal display panel PNL1, and one pixel PX1 is provided for one pixelPX2, but the configuration is not limited to this. For example, onepixel PX2 may be arranged for multiple pixels PX1. For example, onepixel PX2 may be provided for every four pixels PX1.

FIG. 6 is a plan view showing a part of two adjacent pixel electrodesPE1 disposed in the liquid crystal display panel PNL1 and a part of twoadjacent pixel electrodes PE2 disposed in the dimming panel PNL2.

As described above, the pixel electrode PE1 of the liquid crystaldisplay panel PNL1 is disposed in a region surrounded by two adjacentscanning lines GL1 and two adjacent signal lines SL1. Between two pixelelectrodes PE1 adjacent to each other along the first direction X, asignal line SL1 is disposed between two adjacent pixel electrodes PE1along the first direction X, and a distance D1 shown in FIG. 6 , part(a) is provided between the two pixel electrodes PE1. With the distanceD1 thus provided between two pixel electrodes PE1 adjacent to each otherin the first direction X, it is possible to suppress one pixel electrodePE1 from interfering with the other pixel electrode PE1.

On the other hand, the pixel electrode PE2 of the dimming panel PNL2 is,as described above, not provided in the region surrounded by the twoadjacent scanning lines GL2 and the two adjacent signal lines SL2.Therefore, between the two pixel electrodes PE2 adjacent to each otheralong the first direction X, the signal line SL2 is not located, andfurther, between the two pixel electrodes PE2, as shown in FIG. 6 , part(b), only a distance D2, which is shorter than the distance D1 providedabove, is provided between the two pixel electrodes PE2. The distance D2is a value, for example, 10 μm or less, or a value equal to the distancebetween the two line portions LP2 adjacent to each other along the firstdirection X.

According to this configuration, one of the pixel electrodes PE2adjacent to each other along the first direction X interferes with theother pixel electrode PE2, and therefore even if only the pixels PX2including one pixel electrode PE2 are lit for display, part of thepixels PX2 including the other pixel electrode PE2 may be lit fordisplay. However, in the pixels PX2 of the dimming panel PNL2, not onlythe pixels PX2 corresponding to the displaying pixels of the liquidcrystal display panel PNL1, but also the pixels PX2 located therearoundare controlled to be lit for display as a measure against parallax.Therefore, even if part of the pixels PX2 adjacent to the lit anddisplaying pixel PX2 are also lit for display, the display quality ofthe display device DSP is not affected. Conversely, according to theconfiguration shown in FIG. 6 , part (b), the line portions LP2 of thepixel electrodes PE2 can be laid evenly in the dimming area CA, and theopening ratio of the dimming area CA can be improved as compared to thecase where a spacing equivalent to the distance D1 of the liquid crystaldisplay panel PNL1 is provided.

FIG. 7 is a plan view showing the light-shielding film BM2 disposed inthe second transparent substrate SUB22 of the dimming panel PNL2 indetail.

As shown in FIG. 7 , in the dimming panel PNL2, the light-shielding filmBM2 has a shape different from that of the pixel PX2. More specifically,the light-shielding film BM2 includes a first portion BM21, a secondportion BM22, a third portion BM23, a fourth portion BM24, and a fifthportion BM25.

The first portion BM21 is disposed to overlap the scanning line GL2 andthe signal line SL2 in plan view, extends along the first direction X asin the case of the scanning line GL2, and extends along the seconddirection Y while bending in the directions d3 and d4 as in the case ofthe signal line SL2. The second portion BM22 is disposed to overcome thedummy signal line DSL in plan view, and extends along the seconddirection Y while bending in the directions d3 and d4 as in the case ofthe dummy signal line DSL.

The third portion BM23 is disposed to overlap the switching element SWin plan view, electrically connected to the respective scanning line GL2and the respective signal line SL2. The fourth portion BM24 is a portionequivalent to the third portion BM23 of the dummy signal line DSL, andis arranged in a shape similar to that of the third portion BM23 in oneend of the dummy signal line DSL. Thus, even though there is noswitching element connected to the dummy signal line DSL, when thefourth portion BM2, which has a shape similar to that of the thirdportion BM3, the light-shielding films BM2 can be evenly distributed tothe pixel PX2, thus suppressing uneven brightness.

The fifth portion BM25 is disposed to overlap in plan view the spacer tomaintain the gap (spacing) between the first transparent substrate SUB12and the second transparent substrate SUB22.

Note that FIG. 7 illustrates an example case where the light-shieldingfilm BM2 includes the first portion BM2 1 to the fifth portion BM25, butthe dimming panel PNL2 is not easily affected by outdoor light, andtherefore the light-shielding film BM2 may have such a structure thatpart of the first portion BM21 to the fifth portion BM25 are omitted.

For example, as shown in FIG. 8 , the light-shielding film BM2 may havesuch a shape that part of the first portion BM21 to the fifth portionBM25 is omitted from the shape shown in FIG. 7 . Alternatively, as shownin FIG. 9 , the shape of the light-shielding film BM2 may have such ashape that the first portion BM21 to the fourth portion BM24 are omittedfrom the shape shown in FIG. 7 . According to the shape of thelight-shielding film BM2 shown in FIGS. 8 and 9 , the opening ratio ofthe pixels PX2 can be improved by the amount to the extent that thelight-shielding film BM2 is omitted.

In the following descriptions, the effects of the display device DSP ofthis embodiment will be described using a comparative example. Note thatthe comparative example is intended to illustrate some of the effectsachievable by the display device DSP, and the effects common to thecomparative examples and the present embodiment are not excluded fromthe scope of the present invention.

FIG. 10 is a plan view showing a pixel PX2′ disposed in a dimming panelaccording to the comparative example. The pixel PX2′ of the comparativeexample is different from that of the embodiment in that it is disposedin a region surrounded by two adjacent scanning lines GL2 and twoadjacent signal lines SL2, and a pixel electrode PE2′ contained in thepixel PX2′ has a shape which fits the region surrounded by the twoadjacent scanning lines GL2 and the two adjacent signal lines SL2.

Generally, the bending shape of a plurality of line portions whichconstitutes a pixel electrode is optimized, and it is considered to bepreferable that the line portions of the pixel electrode be bent alongthe directions d1 and d2 which intersect the second direction Y at anangle 91. Therefore, if the pixel electrodes are formed into a shapethat fits the region surrounded by the two signal lines SL2 having abending shape which bends along the directions d3 and d4 intersectingthe second direction Y at an angle θ2, unlike the optimized bendingshape of the line portions and the two adjacent scanning lines GL2, thepixel electrode PE2′ is broken at a bending edge of the pixel electrodePE2′, or the line portion LP2′ is formed into a shape which is differentfrom the optimal shape as shown in FIG. 10 . Due to this structure, whenthe liquid crystal layer is driven, alignment errors occur in the endportion of the pixel electrode PE2′, resulting in degradation in thedisplay quality of the display device.

By contrast, in this embodiment, the pixel electrode PE2 contained inthe pixel PX2 is formed not into a shape which fits the regionsurrounded by the two adjacent scanning lines GL2 and the two adjacentsignal lines SL2, but into a shape different from that of the region,and thus all the line portions LP2 which constitute the pixel electrodePE2 are formed into an optimized shape. With this structure, if theliquid crystal layer LC2 is driven, alignment errors do not occur at theend portion of the pixel electrode PE2 and the display quality is notdegraded because the line portion LP2 contained in the pixel electrodePE2 is not cut in the middle, or the shape of the line portion LP2becomes different from the optimized shape, unlike the comparativeexample shown in FIG. 10 . In short, the display quality of the displaydevice can be improved compared to that of the comparative example.

Further, in this embodiment, the pixel electrode PE2 contained in thepixel PX2 can be formed into a shape similar to that of the pixelelectrode PE1 of the liquid crystal display panel PNL1, and thereforewhen the liquid crystal display panel PNL1 and the dimming panel PNL2are superimposed on each other, the pixel electrode PE1 and the pixelelectrode PE2 are not misaligned with each other.

Note that this embodiment illustrates an example case where the bendingdirection of the line portions LP2 that constitute the pixel electrodePE2 of the dimming panel PNL2 is opposite to the bending direction ofthe signal line SL2 of the dimming panel PNL2, but the bending directionof the line portion LP2 may be the same as the bending direction of thesignal line SL2 as shown in FIG. 11 . Even in this case, the followingconfigurations remain unchanged. That is, the bending angle of the lineportions LP2, which constitute the pixel electrode PE2 is different fromthe bending angle of the signal line SL2, and all the line portions LP2are formed to have an optimized shape, and a plurality of line portionsLP2 are formed to extend in the second direction Y so as to cross(straddle) the signal line SL2 in plan view. Therefore, the occurrenceof the alignment errors can be suppressed, and it is possible to improvethe display quality of the display device.

According to one embodiment described above, the display quality of thedisplay device DSP comprising two display panels, namely, a liquidcrystal display panel PNL1 and a dimming panel PNL2, can be improved.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions.

What is claimed is:
 1. A display device comprising: a first displaypanel including a display area for displaying images; a second displaypanel including a dimming area for controlling brightness of the displayarea; and an adhesive layer which adheres the first display panel andthe second display panel to each other, the first display panelcomprising: a first scanning line extending along a first direction, afirst signal line extending in a second direction intersecting the firstdirection while bending in a first bending direction, a first pixelelectrically connected to the first scanning line and the first signalline, the first pixel including a first pixel electrode including aplurality of first line portions extending parallel to the first signalline, and the second display panel comprising: a second scanning lineextending along the first direction, a second signal line extending inthe second direction while bending in a second bending direction, and asecond pixel electrically connected to the second scanning line and thesecond signal line, the second pixel including a second pixel electrodeincluding a plurality of second line portions intersecting the secondsignal line in plan view.
 2. The display device of claim 1, wherein theplurality of second line portions extend in the second direction whilebending in the first bending direction and cross the second signal linein plan view.
 3. The display device of claim 1, wherein a bending shapeof the first signal line is different from a bending shape of the secondsignal line, and the second signal line bends in an opposite side to thefirst signal line.
 4. The display device of claim 1, wherein a bendingangle of the first signal line made by the second direction and thefirst bending direction is smaller than a bending angle of the secondsignal line made by the second direction and the second bendingdirection.
 5. The display device of claim 1, wherein a bending shape ofthe plurality of first line portions and a bending shape of theplurality of second line portions are the same as each other.
 6. Thedisplay device of claim 5, wherein a bending shape of the first signalline is the same as the bending shape of the plurality of first lineportions, and a bending shape of the second signal line is differentfrom the bending shape of the plurality of second line portions.
 7. Thedisplay device of claim 1, wherein the plurality of second line portionsare disposed to be spaced apart from each other at equal intervals alongthe first direction.
 8. The display device of claim 7, wherein thesecond pixel electrode and an other second pixel electrode disposedadjacent to the second pixel electrode along the first direction arespaced apart from each other at an interval equal to a distance betweentwo second line portions adjacent to each other along the firstdirection.
 9. The display device of claim 8, wherein an interval betweenthe second pixel electrode and the other second pixel electrode is 10 μmor less.
 10. The display device of claim 1, wherein the second displaypanel further comprises a first substrate, a second substrate opposingthe first substrate, a liquid crystal layer disposed between the firstsubstrate and the second substrate, a spacer which maintains an intervalbetween the first substrate and the second substrate, and alight-shielding film, and the light-shielding film is disposed in aposition overlapping the spacer in plan view.
 11. The display device ofclaim 10, wherein the light shielding film is further disposed in aposition overlapping the switching element which electrically connectsthe second scanning line and the second signal line thereto in planview.
 12. The display device of claim 11, wherein the light-shieldingfilm is further disposed in a position overlapping the second scanningline and the second signal line in plan view.